The Effects of Cryomilling CNTs on the Thermal and Electrical Properties of CNT/PMMA Composites

Abstract

Abstract:In this study, the cryomilling of carbon nanotubes (CNTs) was carried out to accomplish better dispersion without using any hazardous chemicals. Accordingly, different samples of CNTs were prepared by varying the milling speed (10, 20, and 25 Hz) and time (5, 10, and 15 min) and incorporated into the poly(methyl methacrylate) (PMMA) matrix. The changes of the morphology were analyzed by utilizing a field emission scanning electron microscope (FESEM) and a high-resolution transmission electron microscope (TEM). Qualitative analysis of the cryomilled CNTs was carried out using Raman spectroscopy, and their surface area was determined via Brunauer-Emmett-Teller (BET) analysis. Subsequently, thermogravimetric analysis was conducted to evaluate the thermal properties, whereas the surface resistivity and electromagnetic interference shielding effectiveness for the electrical conductivity were also examined. It was observed that the composite with Cr-20-10 showed better thermal stability and lower resistivity in comparison to the others because, as the cryomilling time and frequency increased the distribution, dispersion and surface area also increased. Consequently, a better interaction between CNTs and PMMA took place.

Acrylic Pressure-Sensitive Adhesive Reinforced with Aluminum Nitride and Its Thermal Properties: Effect of Surface Treatment and Particle Size

“…The TGA pattern of neat PSA shows two-steps while other samples have a three-steps degradation pattern. These two steps of degradation in neat PSA are ascribed to the degradation of polymer chains (at around 290 °C) and total decomposition of the polymer (at around 370 °C) in PSA, respectively [20]. In all the AlN reinforced PSA composites, one extra step at around 100 °C, ascribed to the adsorbed moisture on AlN particles due to their hygroscopic nature, is also observed.…”

Study on morphology, molecular weight and thermal properties of composite microspheres prepared by controlling feeding ways and reaction time

“…34 It should be observed that the thermal property of the P(M-M)/CNTs-d microspheres is improved much less compared with that of P(M-M)/CNTs-6. This thermal stabilization effect is mostly due to that CNTs improve thermal stability by restricting the mobility of the polymer chains and acting as heat barriers.…”

“…This thermal stabilization effect is mostly due to that CNTs improve thermal stability by restricting the mobility of the polymer chains and acting as heat barriers. 34 It should be observed that the thermal property of the P(M-M)/CNTs-d microspheres is improved much less compared with that of P(M-M)/CNTs-6. The thermal property is affected by the carbon nanofillers structure quality within the matrix, restricted mobility of the polymer chains, dispersion of nanofillers, and the interfacial adhesion between nanofillers and the polymer matrix.…”

Epitaxial Crystallization of Precisely Methyl-Substituted Polyethylene Induced by Carbon Nanotubes and Graphene

“…It is widely recognized that the mechanism of epitaxial crystallization is based on some certain crystallographic matches [1], and the mismatching of the contact lattice planes between the substrate and polymers cannot exceed 15%. For example; one-dimensional or two-dimensional lattice matches generate special interactions between the polymer chains and the substrate in the contacting interface which can alter not only the crystal structure and morphology of polymers, but the crystallization kinetics [2][3][4][5][6]. One-dimensional carbon nanotubes (CNTs) and two-dimensional graphene are frequently used as substrates to induce polymer crystallization because of their high surface area.…”